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The radius r of the circle below is 11cm​

The radius r of the circle below is 11cm​-example-1
User Simon Mark Smith
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2 Answers

22 votes
22 votes
Answer: a= 379.94


Step 1: Rewrite equation

As the first step, it is helpful to rewrite the equation for the area of a circle. The a will stand for area, the π will stand for pi, and the r will stand for radius.

a= πr²

Step 2: Substitute numbers

For step 2, we will substitute information. We are made aware that the radius is 11, so we will replace r with 11. To make the equation easier to understand, we will add the multiplication sign in between pi and 11 squared.

a= π•11²

Step 3: Solve using PEMDAS

To solve this equation, we will follow the order of operations, also referred to as PEMDAS, standing for parentheses-exponent-multiplication-division-addition-subtraction. According to this formula, the first thing we will need to do is solve for the exponent. To do so, let’s find the squared value of 11.

a= π•11²
a= π•121

For the next part, we need to multiply 121 by π for the final answer. For the sake of this problem, we will leave pi as 3.14. This can always be replaced by putting the pi symbol into your calculator, though we will use 3.14.

a= 3.14•121
a= 379.94

This is your answer. Hope this helps! Comment below for more questions.
User Isaac Lyman
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3.0k points
12 votes
12 votes

Answer:


{ \bf{area = \pi {r}^(2) }} \\ = 3.14 * {11}^(2) \\ = 380.1 \: {cm}^(2)

User Hellomichibye
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3.1k points